Schneider F3SP71-4S Safety PLC Module
The Schneider Electric F3SP71-4S is a failsafe programmable logic controller (PLC) module from the Modicon M340 safety platform. It is designed to execute safety logic up to SIL 3 (IEC 61508) and PL e (ISO 13849-1). The module integrates two Ethernet ports and a dedicated safety bus interface, enabling high-integrity control for emergency stop, light curtain, and two-hand monitoring applications in industrial machinery.
Processor and Memory
The F3SP71-4S uses a dual‑core lockstep ARM Cortex‑R4 processor at 300 MHz, with 8 MB flash memory for the safety program and 4 MB RAM for data. Program capacity: up to 5000 safety function blocks. The module includes a real‑time clock (RTC) with battery backup (CR2032, 5 years). Scan time for safety tasks is programmable from 2 ms to 50 ms.
Safety I/O and Expansion
The controller does not have onboard I/O but communicates via the Modicon M340 safety backplane (X80) with BMX series failsafe I/O modules (e.g., BMX SDI 1604, BMX SDO 1604). Up to 7 safety I/O modules can be connected locally. For distributed safety, the F3SP71-4S acts as a PROFIsafe master over the built-in Ethernet ports.
Communication Ports
2 x Ethernet (10/100) with integrated switch, supporting PROFINET (PROFIsafe), Modbus TCP, and EtherNet/IP.
1 x USB (mini-B) for programming and firmware updates.
1 x RS-232 (9-pin D-sub) for serial non‑safety communication.
Safety Certifications
SIL 3 (IEC 61508:2010).
PL e (ISO 13849-1).
TÜV certified (certificate no. 968/EC 634).
EN 62061, EN 61800-5-2 for drive safety.
Power Supply and Environmental
Supply voltage: 24V DC (19.2–28.8V). Power consumption: 6 W typical. Dimensions: 105 mm height x 35 mm width x 130 mm depth. Weight: 0.25 kg. Mounting: DIN rail (EN 60715). Operating temperature: -10°C to +60°C; storage: -40°C to +85°C. Humidity: 10% to 95% non-condensing. Protection class: IP20. Vibration: 3 g (10–150 Hz).
Programming Software
EcoStruxure Control Expert (formerly Unity Pro) version 14.0 or higher with Safety Add‑on. Languages: FBD (Function Block Diagram) for safety logic, and LAD/ST for standard logic. The module supports online change of safety parameters without stopping the safety CPU (limited).
Diagnostics and LEDs
LEDs: RUN (green), ERR (red), SAFE (yellow), ETH1/ETH2 (link/activity), and a 2‑digit display for error codes. The module stores the last 100 safety events in non‑volatile memory. A watchdog timer (WDT) with configurable timeout (1–100 ms) ensures failsafe operation.
Typical Applications
Safety logic for packaging machines, robotics cells, press brakes, and conveyor systems. The integrated PROFIsafe allows connection to drives (e.g., Altivar) for safe torque off (STO).
Ordering and Documentation
Schneider order number: F3SP71-4S. Manual: Modicon M340 Safety PLC User Guide (EIO0000003265).





